Kofi Annan The battle to find the funds Climate change is an all encompassing threat - threat to health, security, food production and to our ecosystems. Leaders must take decisive action in Bali to come to grips with climate change. The scientific evidence is compelling and alarming. We must sustain a two-pronged approach: mitigation and adaptation. The only suitable response is a binding international framework agreement to curb greenhouse gas emissions beyond the Kyoto protocol which expires in 2012. We have to take steps to increase the resilience of vulnerable communities to the impact of climate change. In order to achieve the global development agenda, we must integrate environmental policies with social and economic policies. It will take huge resources to fund the adaptation to the actual impact of climate change on communities around the world. Funding must be a part of any serious solution to the climate change predicament we face. Kofi Annan was the seventh secretary-general of the United NationsDavid Bellamy Conservation, not carbon doom Consensus at Bali (despite the air miles) should replace the unproven big stick of carbon doom and gloom with an interactive map highlighting the fact that both rich and poor will prosper from good science, engineering and technologies already in the pipeline. No need for debilitating taxes, as environmental rewards will flow from the efficient use of energy, water and other resources. Directing funding to conserve the worlds natural areas, their soils and biodiversity is the bedrock of this bottom line. Each one is a solar powered gene bank, living carbon allowing local communities to stitch their patch and hence the world back into more sustainable working order. The green renaissance is in your hands, please be part of it! Professor David Bellamy is a botanist, broadcaster and campaignerGiovanni Bisignani A plane that doesn't pollute Aviation is built on breakthroughs. In 50 years, we went from the Wright Brothers to the jet engine and trans-Atlantic travel. And today we are global mass transit for 2.2 billion people. What's possible in the next 50 years? The breakthrough I want to see is a plane that does not pollute - reducing aviation's 2% share of carbon emissions to zero. Some building blocks already exist - fuel cell technology, solar power and fuel from algae. Airlines, manufacturers and fuel suppliers are aligned and hard at work. What's missing is government commitment to coordinate and fund breakthrough research. Anything is possible. That's the spirit of our history - and it will define our future. Giovanni Bisignani is director general of the International Air Transport AssociationRichard Branson Halt rainforest destruction The climate is already changing and we need to find urgent ways to mitigate that change immediately and maintain as much biodiversity on the planet as possible. The most positive but realistic thing that governments could agree in Bali is to halt the cutting down of virgin tropical rainforests with immediate effect and agree a method by which the major economies, big multinationals and other carbon offset groups could pay for it. Why is this so important? The next five years of carbon emissions from burning rainforests will alone be greater than all the emissions from air travel since the Wright brothers first flight in 1903 until at least 2025. Richard Branson is the chairman of Virgin GroupBrian Eno Electoral reform comes first It seems like an unambitious idea, but I think the most important thing we could do to deal with climate change is to change our voting systems. Right now, many people who care about climate change don't dare to vote for the parties who have shown a willingness to deal with it: in particular the Greens and the Liberal Democrats. Why? Because our "first past the post system" makes a vote for a minority party seem like a waste. This seems to me a way out of the electoral trap that we're in now, where many people vote negatively - to exclude - rather than positively - to include. Brian Eno is a musician and campaignerLeon Fuerth A way to trap carbon dioxide The single breakthrough that would be a game-changer is technological: it would involve an efficient method for trapping carbon dioxide as it is generated, before it can enter the atmosphere. The hurdles are difficult to clear, however: it would have to be a stable method; its costs would have to make it affordable not just in countries like the US, but in rapidly developing countries like China and India. Even such a breakthrough would have to be coupled with a profound change of mind about relying on massive consumption of carbon based fuels. It would have to be used as a way out of our dependence on these fuels, not as a free pass to go on as before. In every instance, a profound change of public and official attitude is needed, and Bali can help that along. Leon Fuerth is former national security adviser to Vice President Al GorePaul Golby Developed nations' duty A global problem demands a global solution. All the developed nations must signal their commitment to new long term reduction targets and underpin the emergence of a global carbon market. This, together with a commitment to urgently develop and demonstrate all forms of low carbon energy technology, from efficient micro-generation in homes to industrial scale projects to capture carbon from the world's fossil power plants, will give nations, businesses and communities the incentive and confidence to invest in radical measures. Dr Paul Golby is chief executive of E.ON UKZac Goldsmith Make leaders feel the pressure We can try to persuade everyone - through books and extravagant concerts - to change their ways. But if we're honest, how many of the planets' 6 billion people will actively respond? Call me a pessimist but I'm not holding my breath, not least because a vast number of people cannot afford to make meaningful green choices. Today if you want to travel by train, eat organic food or drive a clean car, you need to pay more. The alternative is to demand proper leadership from government so that green choices become available to everyone. It has the tools. The single most important thing we can all do is to pile the pressure on our leaders. We must let them know we expect them to do the right thing, and that they will be rewarded for doing the right thing. Zac Goldsmith is a Conservative candidate and environmental adviser to the partyMayer Hillman Allocate carbon equitably The equitable allocation of carbon emissions across the world's population and its application through mandatory tradable personal carbon rationing is the only realistic way forward. Support is gathering pace - German chancellor Merkel backed it this summer. Technology, increased energy efficiency and green taxation cannot conceivably ride to the rescue within the timescale remaining for sufficiently effective action. Dr Mayer Hillman is senior fellow emeritus at the Policy Studies Institute and author of How We Can Save the PlanetIsabel Hilton Policy has to follow science The single most important breakthrough - which must form the basis of action - would be acknowledgment that policy must follow science, however difficult that is. We need an agreement at Bali of an upper stabilisation limit that recognises that we cannot allow the global average temperature to rise above two degrees centigrade. In order to avoid a greater rise and the consequent risk of runaway effects, we must agree that concentrations of greenhouse gases should not be allowed to rise above 400 to 450 part per million, CO2 equivalent. Until now, few national leaders have had the courage to make this commitment. Without it, we are plagued by shifting targets and lack of clarity. With a clearly defined target, policy can be designed to meet it. Isabel Hilton is editor of Chinadialogue and OpenDemocracyJeremy Leggett The renewable remedy I can only agree with the original UK government energy review of 2003, which concluded that "solar energy could meet world energy demand using less than 1% of land now under crops and pasture." We wouldn't need the arable land, actually. We could use the tops and sides of buildings. Hand-in-hand with energy conservation and efficiency, I have no doubt that solar can lead the renewables family in powering our world cleanly a few decades from now. But we will need to overcome the vested interests - or enlighten them - if we are to get to the promised land. Jeremy Leggett is chairman of Solar-century and author of The Carbon WarMark Lynas A global target for a 80% cut I know this is probably too much to ask, but it would be great if world leaders could get together and actually hammer out an agreement to stabilise the world's climate. Bali and Kyoto are important, but are at best incremental steps towards a long-term goal that no-one seems to want to talk about. A real breakthrough would be to agree on a worldwide target for emissions cuts of 80% by 2050 in order to keep global warming from passing the magic two degrees mark. That's it really. We can work out the nitty gritty of who does what later. Mark Lynas is the author of Six Degrees: Our Future on a Hotter PlanetFrank Loy The great American potential The answer is straightforward and, for an American, a bit embarassing. It would be for the US to adopt, at last, a national programme to reduce GHG emissions: a meaningful emissions cap covering all or most of the economy, with short and mid-term targets, a trading system to reduce costs of compliance, and complementary policies to promote low emission technologies where price signals don't work. US domestic action is a precondition for a meaningful agreement involving all key nations. If the US continues to dither and not adopt a domestic law, not only will China, India (and maybe even Japan) reject possibly costly actions, but the US Senate will resist approving an international climate treaty. Frank Loy was US under secretary of state for global affairs and chief climate negotiator from 1998 to 2001Wangari Maathai Develop and protect If there were a technological breakthrough that offered an affordable and accessible way to reduce global reliance on fossil fuels we would most certainly see a major change in the rate of global warming. In connection with this, if a decision was made to protect the major forests of the world, and in particular the Congo, the Amazon, and the forests of Southeast Asia, that, in addition to the breakthrough in technology, would make all the difference for our planet. Dr Wangari Maathai is a Kenyan environmental activist and Nobel Peace laureateGeorge Marshall From knowing to believing For 20 years the assumption has always been that if only people knew how serious climate change is surely they will act. But knowing something and believing in it are not the same. Climate change is so huge, so destabilising, so far outside our usual experience that our natural response it to push it away. People are still clutching on to any argument that suggests that it is still unproven, in the future, someone else's problem or someone else fault. Once you have accepted and internalised climate change you are not taking action to "save the planet" - you are doing it as a statement of who you are and what you believe. And that is how to really change things. George Marshall is the author of Carbon Detox and blogs at Climatedenial.orgGeorge Monbiot Fairness and simplicity on CO2 There should be an equal allocation, worldwide, of the right to produce carbon dioxide. Our rations can be tradeable - people may use more than their share if they are prepared to buy it - but the revenue should be returned to those who use less. This system works because it is just, easy to understand, requires very little policing and creates powerful incentives to use low carbon technologies. George Monbiot is the author of Heat: How We Can Stop the Planet BurningRajendra K Pachauri Radical change to transport Each individual has to be part of the global solution, so that collectively the human race can meet this challenge effectively. In my view the most feasible option would be to bring about radical changes in our transportation habits. What every individual can do is to ensure that places that one can easily walk to are covered on foot. Each individual must set as a goal actions to promote low carbon-dioxide emissions from transportation that he or she is responsible for. Dr RK Pachauri is chairman of the Nobel peace prize winning Intergovernmental Panel on Climate Change

Jonathon Porritt Real steps on the carbon price The Bali Consensus is that we must reduce emissions of CO2 by at least 80% by 2050. As Sir Nicholas Stern made so clear, that will only happen if the price of a tonne of CO2 gets as high as possible as fast as possible - globally. Governments know this. They also know that trading schemes (like the EU's Emissions Trading Scheme) will take far too long to get us to that point. So, in an ideal world, they need to do three things: determine what price level is required to achieve the 80% cut by 2050; set a "floor price" for CO2 to kick in no later than 2012; agree the "price milestones" between 2012 and 2050. Almost everything else will follow. Jonathon Porritt is chairman of the UK sustainable development commission and founder director of Forum for the Future

Jeremy Rifkin A third industrial revolution The pivotal economic changes in world history occur when new energy regimes converge with new communication regimes. Today, the technology that made possible the IT and internet revolutions is coming together with renewable energy and hydrogen and fuel cell storage technology to create the foundation for a third industrial revolution and a post-carbon, post-nuclear era. In 25 years, businesses and homeowners will produce much of their own power with locally available renewable energy, and store it in the form of hydrogen. Surplus energy will be shared with others via an intelligent "intergrid" just as we now produce our own information and share it with others via the internet. This revolution will help usher in a near zero-emission energy era. Jeremy Rifkin is an adviser on climate changet to the EU commissionJoseph Romm A moratorium on old coal The science is in and we've run out of time for further delay. It's time for a bold step to reverse emissions trends immediately - a global moratorium on the construction of coal plants that don't capture and sequester their carbon. As part of the moratorium, we need: an aggressive energy-efficiency strategy to replace the need for most new power plants; direct assistance to countries like China and India to build alternative zero-carbon plants; extensive testing of carbon-capture technology; and a global effort to identify and certify permanent geologic repositories for carbon. Joseph Romm is senior fellow at the Centre for American Progress and editor of ClimateProgress.org

Nicholas Stern The rich must take the lead We need a global agreement to reduce greenhouse gas emissions with the rich countries leading the way on targets and trading. The overall targets of 50% reductions in global emissions by 2050 (relative to 1990) agreed at the G8 summit in Heiligendamm in June are essential if we are to have a reasonable chance of keeping temperature increases below 2 or 3°C. Within these global targets, the rich countries should aim for a more ambitious reductions target of at least 80% - either made directly or purchased via a global mechanism for trading emissions. Trade in emissions has the double benefit of keeping costs down and providing glue for the global deal. Sir Nicholas Stern is adviser to the British government on the economics of climate change and development

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